Editorial
Foreign exchange market efficiency is commonly investigated by Fama-regression tests of uncovered interest parity (UIP). In this paper, the author conjectures a speculative UIP relationship which implies that exchange rate changes comprise a time-varying risk component in addition to the forward premium. This suggests that the forward premium anomaly reported in previous research potentially stems from omitting this component in UIP tests and that the popular carry-trade strategy can be rationalized to some extent. Moreover, while related work focuses on the Famaregression slope coefficient, the author shows that also the intercept is important for judging the economic significance of currency speculation. Empirically, the author finds support for speculative UIP and the existence of a risk-premium. Furthermore, although carry-traders are able to collect some risk-premia, currency speculation does not yield economically significant excess returns, which suggests that foreign exchange markets are speculatively efficient. Disregarding the Fama-regression constant, however, leads to distortions in the assessment of economic significance and induces spurious rejection of speculative efficiency.